(A) Alteration or relocation of a watercourse.
(1) A watercourse or drainway shall not be altered or relocated in any way that in the event of a base flood or more frequent flood will alter the flood carrying characteristics of the watercourse or drainway to the detriment of upstream, downstream, or adjacent locations.
(2) No alteration or relocation shall be made until all adjacent communities that may be affected by such action and the Nebraska Department of Natural Resources have been notified and all applicable permits obtained. Evidence of such notification shall be submitted to the Federal Emergency Management Agency.
(B) Encroachments.
(1) When proposing to permit any of the following encroachments, the standards in division (B)(2) of this section shall apply:
(a) Any development that will cause a rise in the base flood elevations within the floodway; or
(b) Any development in Zones A, A1-30, and Zone AE without a designated floodway that will cause a rise of more than one foot in the base flood elevation; or
(c) Alteration or relocation of a stream; then
(2) The applicant shall:
(a) Apply to FEMA for conditional approval of such action via the Conditional Letter of Map Revision process (as per Title 44 of the Code of Federal Regulations, Chapter 1, Part 65.12) prior to the permit for the encroachments; and
(b) Supply the fully approved package to the Floodplain Administrator including any required notifications to potentially affected property owners.
(C) Floodway Overlay District.
(1) Within any floodway, any new construction or substantial improvements shall be prohibited.
(2) Standards for the Floodway Overlay District:
(a) New structures for human habitation are prohibited.
(b) All encroachments, including fill, new construction, substantial improvements, and other development must be prohibited unless certification by a registered professional engineer or architect is provided demonstrating that the development shall not result in any increase in water surface elevations along the floodway profile during the occurrence of the base flood discharge. These developments are also subject to all the standards of §§ 154.40-154.42.
(c) In Zone A areas, obtain, review, and reasonably utilize any flood elevation and floodway data available through federal, state, or other sources, including studies done under § 154.42(H), in meeting the standards of this section.
(3) Only uses having a low flood-damage potential and not obstructing flood flows shall be allowed within the Floodway Overlay District to the extent that they are not prohibited by any other ordinance. The following are recommended uses for the Floodway Overlay District:
(a) Agricultural uses such as general farming, pasture, nurseries, and forestry
(b) Residential uses such as lawns, gardens, parking, and play areas
(c) Nonresidential uses such as loading areas, parking, and airport landing strips
(d) Public and private recreational uses such as golf courses, archery ranges, picnic grounds, parks, and wildlife and nature preserves.
(Ord. 734, passed 3-8-2023)